Traction-elevator.



C. 0. PEARSON. TRACTION ELEVATOR. APPLICATION I'ILED APR. 5, 1909.

1,029,627, Patented June 18, 1912.

2 BHEETB-SHEET 1.

G. O. PEARSON.

TRACTION ELEVATOR; APPLICATION FILED APR. 5, 1909.

' Patented June 18, 1912.

2 SHEETS-SHEET 2.

' WITNESSES:

ATTORNEY CHARLES O. PEARSON, OF NEW YORK, N. Y.

TRACTION-ELEVATOR.

oaacer.

Specification of Letters Patent.

Patented June 18, 1912.

AppIication filed April 5, 1909. Serial No. 487,866.

To all whom it may concern:

Be it known that I, CHARLES O. PEARSON, a citizen of the United States,and a resident of the borough of Brooklyn, in the county of Kings, cityand State of New York, United States of America, have invented certainnew and useful Improvements in Traction-Elevators, of which thefollowing is a specification.

My invention relates to traction elevators and its object is to improveupon elevators of this type, and to provide a novel and eiii cientapparatus for driving them.

I will describe my invention in the following specification and pointout the novel features thereof in the appended claims.

Referring to the drawings, Figure 1 is a side elevation of the drivingmechanism and some of its connected parts, and also shows a wiringdiagram with certain electrical connections which may be used incarrying out my invention. Fig. 2 is a side elevation of one of thedriving sheaves with a part broken away to show its construction. Fig. 3is a side elevation of a modified arrangement of some of the parts shownin Fig. 1. Fig. 4 is an end elevation of a portion of the drivingmechanism together. with a car and counterweight and their connectingdriving strips. Fig. 5 is an end elevation of one of the electromagneticbrakes used with this apparatus. In Fig. 6 is shown the manner in whichthese parts may be arranged when it is desired to have the drivingmachinery at a point below the top of the shaft.

Like characters of reference designate corresponding parts in all of thefigures.

10 designate an elevator-car and 11 its counterweight. These areconnected together by a series of flat strips 12, 13 and 14 of flexiblemetal. These strips are to be carried over driving sheaves which will bemore fully described hereinafter and affixed to the car and to thecounterweight in any desired manner.

Referring to Fig. 1, 20' is abase-plate upon which the various parts ofthe driving machinery may be mounted. 21 is an electric motor mountedupon this base. 22 is its shaft, and 23 is a driving sheave upon theouter end of the shaft, which driving sheave is shown somewhat in detailin Fig. 2. In this figure it may be seen that it has a flat drivingsurface which may, if desired. be covered with a facing 24 of leather orother suitable material. At either side of this surface are flanges 25,the distance between which is somewhat greater than the width of thestrips which run between them. is a brake-pulley keyed to the shaft 22.31 and 32 are brake levers which are pivoted at 33 and 34 and carrysuitable brake-shoes. These shoes are arranged to be forced against thesurface of the pulley 30 by means of a compression spring 35 acting upona rod 36, one end of which is connected with the free ends of brakelevers 31 and 32 by toggle links 37 38 designates a solenoid to the coreof which the rod36 is connected. This solenoid is so arranged that whenit is energized it will draw in its core against the action of spring35, and, through the mechanical connections above pointed out, willrelease the brake-shoes. The other motors are designated in Fig. 1 bythe numerals 26 and 28 and their shafts by 27 and 29. As the variousparts of these motors and their driving sheaves and brake mechanisms aresimilar to those above pointed out, further description of them is notneces sary.

I will now trace the circuits which are shown in the wiring diagram as asimple manner of connecting the various parts of the hoisting apparatusand at the same time will describe the operation of this invention.

and designate mains from a suitablesource of electrical supply. These,after passing through a switch 40, are connected with certain stationarycontacts of an electromagnetically actuated reversing switch, theactuating magnets or solenoids of which are designated by 41 and 42. isa manually operated controlling switch which is preferably located inthe car 10. This switch comprises a movable contact lever 51 which isconnected with the positive main by a conductor 52. 53 is a stationarycontact in the controlling switch which is connected. by a conductor 54with one end of the winding of solenoid 41, the other end. of which isconnected at 55 with the negative main. When an operator moves thecontact lever 51 to the. left, he therefore closes a circuit throughsolenoid 41, which then raises certain movable contacts. These,cooperating with some of the stationary contacts of the reversing switchwhich have been before mentioned, cause the positive main to beconnected through conductor 43 and an automatic rheostat and conductor44 with one of the armature terminals of each of the motors, and at thesame time will cause the negative main to be connected with the otherarmature terminals of each motor through a conductor 45. 46 is a conductor from the negative main to one of the terminals of the shunt fieldwinding of each of the motors and to one of the terminals of each of thebrake solenoids. When the lefthand portion of the reversing switch hasbeen actuated it will cause circuits to be completed from the positivemain through conductor 47, the contacts of the reversing switch, andconductor 48 through all of the motor shunt fields and through all ofthe brake solenoids. Now the brakes will be released and the motors willrotate slowly in one direction. This rotation of the motors will beimparted to the driving sheaves, and through the flat metallic stripswill cause the car and counterweight to be driven in oppositedirections. It is to be noted that there is no mechanical connectionbetween the shafts of the different motors except that through thedriving strips. An inclependent driving force will therefore be exertedupon each of these strips and the relative speeds of the motors will beautomatically adjusted without putting undue strains upon the hoistingapparatus or the driving strips. The driving sheaves may be of the samediameter or of diiferent sizes as will be pointed out hereinafter, andthe normal speed of the motors may be made to be somewhat closelyproportional to the desired peripheral speed of the sheaves so as tominimize the amount of this self adjustment of their relative speeds. Afurther movement of the controlling switch lever 51 to the left willbring it onto a stationary contact 56 which will close a circuit througha conductor 57 and a solenoid 61 of the auto matic rheostat back to thenegative main at- 55. This solenoid 61 is arranged to move a contactlever 62 over a plurality of stationary segments 63 to which resistancecoils 64 are connected to cut this resistance out of the motorarmatures. In order to make this 7 action gradual, a dashpot 65 isconnected with the contact arm. This will cause a smooth and gradualacceleration of the motors and of the driven car.

It is evident that these operations may be reversed as the operator maymove the switch-lever back partway to cut ofi solenoid 61 so thatresistance coils 64 may be again put into series with the motorarmatures to cause them to run slowly or he may move the switch-leverback to its central position when the current will be cut ofi from themotors and the brakes to bring the apparatus to rest. A movement of theswitch-lever 51 to the right will bring it -first onto stationarycontact 58 which is connected through conductor 59 with sole noid 4:2 toactuate the right-hand portion 1 modate strips such as 12 and 12 Ob- Hviously, this number of driving surfaces may be increased if desired. Ido not mean, by describing this method, that I limit myself to anyspecific number of motors, as it is apparent that any desired number ofmotors may be used in this combination.

In Fig. 1 the driving sheaves are shown as being of equal diameters. Thelower ones could obviously be made smaller than those above them if itis desired to have the strips entirely independent of each other. Suchan arrangement is shown in Fig. 1. In Fig. 6, however, the drivingsheaves which are nearer the car are made larger so that the variousstrips overlap one another. In this figure the driving strips 12, 13 and14 are aflixed at 15 to ropes or cables 16 which run over a sheave 17and to the car 10 to which they are suitably attached,

and, in a similar manner, at 18 to cables 19 which run to thecounterweight.

This invention makes possible the employment of a plurality of drivingstrips, each of which is driven by a wide friction surface which may becovered with a comparatively soft facing, and which surfaces not onlyefficiently drive the car while they are in motion, but effectively andsafely hold it while they are at rest. These features are important inthe particular types of tors shown, but obviously the same invention maybe used in conjunction with other forms of elevators and even with otherkind of apparatus. Furthermore, the several eleva- Y prlme movers rotateindependently of each other and readily adjust themselves to therequired relative speeds without putting any undue strains upon thehoisting mechanism, nor subjecting the driving strips to abnormalstresses.

What I claim is 1. A driven member, a plurality of fiat over-lappingmetallic strips afiixed thereto, and separate rotary driving means foreach of the strips.

2. A driven member, a plurality of flat over-lapping metallic stripsafiixed thereto, a rotary driving sheave for each of said strips and anindependent motor for each sheave.

'3. A driven member, a plurality of flat over-lapping metallic stripsaffixed thereto, a plurality of motors and a' plurality of rotarysheaves independently driven by said motors, said sheaves being arrangedto drive said strips.

4. A driven member, a plurality of overlapping fiat metallic stripsaffixed thereto, a plurality of motors, a plurality of sheavesindependently driven by said motors, and a facing for said sheaves ofyieldable material, each of said sheaves being arranged to drive one ormore of said strips.

5. A driven member, a plurality of overlapping flat metallic stripsaffixed thereto, a plurality of driving sheaves, a separate electricmotor for each of said sheaves, said motors being mechanically connectedby said strips, and electrical connections between the motors.

6. In a traction elevator, a car, a plurality of overlapping flatmetallic strips connected therewith, a plurality of rotatable membershaving driving surfaces, each arranged to drive one of said strips, andindependent means for rotating said members.

7 In a traction elevator, a car, a counterweight, a plurality of flatmetallic strips connecting the car and the counterweight, and separatedriving means for each of the strips.

8. In a traction elevator, a car, a counterweight, a plurality of flatmetallic strips connecting the car and the counterweight, a plurality ofrotatable members having driving surfaces, each arranged to drive one ofsaid strips, and independent means for r0- tating said members.

9. In a traction elevator, a car, a plurality of overlapping flatmetallic strips connected therewith, a plurality of sheaves havingcylindrical driving surfaces, each of which surfaces cooperates with oneof the strips, and a motor for each sheave.

10. In a traction elevator, a car, a counterweight, a plurality of fiatmetallic strips between the car and the counterweight, a plurality ofsheaves having cylindrical driving surfaces, each of which surfacescooperates with one of the strips, and an electric motor for eachsheave.

11. In a traction elevator, a car, a counterweight, a plurality of fiatmetallic strips between the car and the counterweight, a plurality ofsheaves having cylindrical surfaces, leather facings affixed to saidsurfaces, each of which surfaces cooperates with one of the strips, anindependent electric motor for each sheave, said motors beingmechanically connected through said strips, and electrical connectionsbetween said motors.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

CHARLES O. PEARSON.

Witnesses EDITH BEBEE, ELLA 'IUci-I.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, D. G.

